Corrosion resisting fire extinguisher



ilnited States Patent CGRRUSTQN RESISTING FIRE EXTEJGUISHER Zhigaiew 3. Lobos, Brooklyn, N. Y., assignor to Stop- Fire, Inc, Brooklyn, N. Y., a corporation of New York Application Ianuary 23, 1953, Serial No. 332,854

4 Claims. (Cl. 264-497) This invention relates to a hand fire extinguisher, or the like, in which a fire extinguishing liquid of the organic halide type, such as carbon tetrachloride or chlorobromethane, is stored for periods of disuse, in containers of such metal as brass, which can be corroded by the liquid or impurities within it, on protracted exposure. This corrosion becomes particularly serious where the type of extinguisher employed contains operating parts which may be corroded to the point of interfering with the operation of the device.

Normally these organic chlorides are considered free from corrosive action on brass, but, in fact, serious trouble has been found to arise from this cause, after prolonged disuse. Whether this arises from traces of free chlorine, or free carbon disulfide in the commercial liquids, or whether there is trace dissociation of the chloride in the presence of the brass, is not clear.

It has heretofore been proposed to guard against such corrosion by the use of metallic magnesium, but such metal is not wholly satisfactory. It does not always completely prevent the corrosion, with a resultant tendency of the valves to stick.

The accompanying drawings Fig. 1 shows a fire extinguisher aving moving parts and valves within the fire extinguishing liquid, in combination with the anticorrosion element, in accordance with this invention. Fig. 2 is a detail cross-section of the anticorrosion element. The details of this extinguisher, itself, will form a separate application, by the assignee of this invention. For the purpose of this invention, it is sufiicient to describe it quite generally. The drawing is a central longitudinal section of the extinguisher, and anticorrosion element.

The numeral is a container, preferably of brass, having a discharge nozzle 11 at one end. Mounted axially within the container is a discharge tube 12 communicating with the nozzle 11, and firmly fixed therein.

Coaxial with the tube 12, and spaced therefrom, is a tubular piston rod 13, on which is mounted for limited sliding movement, a piston 14. This piston moves within a pump cylinder 15, and its movement is so limited that on movement of the piston rod 13, in either direction, the piston will not move until after a sufiicient lost motion is taken up, to cover a valve opening 16 in the one direction, or 16a in the other direction in the piston rod.

Freely rotatable on the tube 12 is a bracket 17, and freely rotatable on the piston rod 13 is a bracket 18. These brackets 17, and 18, each have a bore 170 and 18a, extending through it, parallel to the tube 12, and these bores are connected by a tube 19, whereby the two brackets, and the tube 20 form a frame, freely rotatable by gravity around the axis of the container 10, having a continuous passageway from one end of the container to the other. This passageway is provided with a ball check valve 17b and 1811, at each end, and near each end it is connected by a cross bore 170 and 18c, with the interior 2,765,273 Fatented Oct. 2, 1955 of the cylinder 15. Each of these passageways is closable by a check valve 17d and 18d.

The piston rod 13 is operated by a handle 20, into which the piston rod is screwed, and mounted upon the piston rod is a centering gasket 21, which engages the tube 12, when the handle is in its innermost position, and in that position a gasket 22, within the handle 20 closes the end of the tube 22. As the handle 20 is reciprocated the cylinder 15 and the piston 14 forms a double acting pump, such, that on the upstroke of the piston, liquid will be drawn into the tube 13 from above the piston, through the opening 16, and on the downward stroke, through the opening 16a, and in each case, the liquid will be dis charged through the nozzle 11. The exact construction of the parts is not pertinent to this invention.

in accordance with this invention it has been found that if there is placed in the container a free body of the same metal as the most active of the metals of the alloy, of which the container is made, the corroding action of any of the impurities in the halide comprising the fire extinguishing liquid will be so neutralized by the free body of the metal that no corrosion of the alloy, or of either of the metals contained therein, will take place. Thus, when the container is made of brass, comprising the alloy of copper and zinc, the neutralizing metal is the metallic zinc, preferably in contact with the brass. In the drawing there is shown a coil 23 of zinc Wire, which surrounds the cylinder 15, and lies in contact with it.

The coil form here shown for the Zinc, is for convenience only, and if the tendency to corrosion is appreciable, the metal may comprise a thin metal strip, or a wire havin a large surface area, as for example, eing made starshape, in cross sections. With this construction the extinguisher will remain free from any corrosion, for long periods of disuse, and the extinguisher will correspondingly, remain in readiness for operation. This is believed due to the fact that the free zinc reacts more easily with any trace impurities than the alloyed metal, because, in fact, it is the same metal as the more active of the alloyed metals, it has no added tendency to dissociate th organic halide gas.

The check valves are so directed that the ejected liquid is drawn into the cylinder from the container, through Whichever one of the check valves 17b, or 1817 is at the lower end of the cylinder 15, depending upon how the container is held.

What I claim:

1. A fire extinguisher constructed of brass and adapted to contain an organic halide extinguishing liquid, having therein a surface of metallic zinc exposed to the liquid.

2. A fire extinguisher constructed of brass and adapted to contain an organic halide extinguishing liquid, having therein a surface of metallic zinc in contact with the brass of the extinguisher.

3. A brass fire extinguisher adapted to contain organic halide extinguishing liquid having therein a coil of zinc wire, having a star shape cross section.

4. A brass fire extinguisher adapted to contain organic halide extinguishing liquid having therein a coil of zinc wire, having a star shape cross section and being in electrical contact with the metal of the extinguisher.

References Cited in the tile of this patent UNITED STATES PATENTS 856,361 Neiburg June 11, 1907 1,190,705 Bassett July 11, 1916 1,941,040 Mann Dec. 26, 1933 2,524,511 Butler Oct. 3, 1950 2,563,171 Huthsing Aug. 7, 1951 

1. A FIRE EXTINGUISHER CONSTRUCTED OF BRASS AND ADAPTED TO CONTAIN AN ORGANIC HALIDE EXTINGUISHING LIQUID, HAVING THEREIN A SURFACE OF METALLIC ZINC EXPOSED TO THE LIQUID. 